An $\alpha$ particle is accelerated through a potential difference of $10^6 \ V$. Then the kinetic energy $(K.E.)$ of the particle will be .......... $MeV$.

Why are atoms electrically neutral?

An $\alpha$-particle of energy $4 \text{ MeV}$ is scattered through $180^\circ$ by a fixed uranium nucleus. The distance of the closest approach is of the order of

An elementary particle of mass $m$ and charge $+e$ is projected with velocity $v$ at a much more massive particle of charge $Ze,$ where $Z > 0.$ What is the closest possible approach of the incident particle?

Statement $(A)$: As one considers orbits with higher values of $n$ in a hydrogen atom,the electric potential energy of the atom increases.
Statement $(B)$: In Thomson's model,an atom is a spherical cloud of positive charges with electrons embedded in it.
Statement $(C)$: The orbital picture in Bohr's model of the hydrogen atom was consistent with the uncertainty principle.

Which source is associated with a line emission spectrum?